Egg case making machine



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EGG cAsE MAKING MACHINE Filed March 2, 1951 15 Sheets-Sheet l5 /lVl/E/VTOE GLENN E'. S'LWELL H7' 7' ORNE V Patented Apr. 21, 1953 EGG CASE MAKING MACHINE Glenn E. Stilwell, Riverside, Calif., assigner to Food Machinery and Chemical Corporation, San Jose, Calif., a corporation of Delaware Application March 2, 1951, Serial No. 213,619

20 Claims.

This invention relates to machines for manufacturing nailed boxes and has particular utility in the manufacture of such boxes from box heads, sides and bottoms which are warped.

Heretofore ithas not been possible to use box parts, commonly known as shookj for the machine manufacture cf nailed boxes unless this shook was fairly free from warpage. Certain types of shook which are given to such warpage have been preferred for the construction of nailed boxes for certain uses and it has therefore been necessary to make these boxes by hand.

It is an object of this invention to provide a nailing machine for making nailed boxes which is adapted to employ shook characterized by a degree of warpage heretofore preventing the use of such shook in a nailing machine.

It is another object of the invention to provide a nailing machine for handling shook of this type which will straighten said shook and clamp the same in the true relation the parts have in the finished bcx, and do this automatically just prior to the driving of the nails in each nailing cycle.

A further object is to provide a machine driving a multiple row of nails at once in which the nails are driven iiush with the general level of the work in the plane of said row.

A. still further object is to provide a nailing machine capable of making boxes certain edges 'of the end heads of which have outside cleats and 'certain other edges have not.

The manner of accomplishing the foregoing objects as well as further objects and advantages 'will be made manifest in the following description taken in connection with the accompanying drawings in which:

Fig. 1 is a fragmentary front elevational view of a nailing machine incorporating a preferred embodiment of the invention.

Fig. 2 is a fragmentary side elevational view of the nailing machine in Fig. l taken in the direction of the arrow 2.

Fig. 3 is a side elevational View of the nailing machine in Fig. 1 taken in the direction of arrow 3.

Fig. 4 is an enlarged fragmentary detailed horizontal sectional view taken cn the line filli of Fig. l and illustrating the manner of mounting one of the cam follower rollers which supports the nailing table.

Fig. 5 is an enlarged vertical sectional View taken on the line 5-5 of Fig. 1 and illustrating the cam mechanism for operating the shiftable extensions provided on the outermost .box head fclamp arms of the invention.

Fig. 6 is an enlarged detailed vertical sectional view taken on the line 6-6 of Fig. 5 and illustrates the rebound spring on one of the nail driver bridge frames.

Fig. 7 is an enlarged fragmentary vertical sectional view taken on the line 'i--l of Fig. 1.

Fig. 8 is a fragmentary perspective view of an automatic clamp arm locking cam of the invention, portions of the structure being broken away for illustrative purposes.

Fig. 9 is an enlarged horizontal sectional Yview taken on the line 9 9 of Fig. 1 and illustrating, in plan, the automatic nail driver bridge release mechanism of the invention. Y

Fig. 10 is an enlarged horizontal sectional View taken on the line Iii-I of Fig. l and illustrating the head clamping and side supporting mechanism of the invention.

Fig. 11 is an enlarged fragmentary sectional View taken on the line I-II of Fig. 5 and illustrating the internal construction of the leftwardmost clamp arm of the invention and the one next thereto.

Fig. 12 is a diagrammatic fragmentary perspective view of the leftwardmost clamp arm of the invention and broken away to illustrate the mechanism for actuating the shiftable pressure face extension mounted on said arm.

Fig. 13 is an enlarged fragmentary vertical sectional detailed View taken on the line |3-I3 of Fig. l0 and illustrating the internal construction of the two clamp arms, shown in Fig. 11.

Fig. 14 is a diagrammatic enlarged fragmentary sectional view taken on the line lli--l of Fig. 10.

Fig. 15 is an enlarged fragmentary sectional view taken on the line l 5-l5 of Fig. 1 and showing the bottom back stops raised to inoperative position, and with the side supports and stops raised into position for locating and supporting a side at the beginning of a side nailing cycle.

Fig. 16 is a view similar to Fig. 15 and shows the side supports and stops lowered to inoperative position and the bottom back stops lowered into position for limiting the backward movement of the bottom when this is placed in the machine before starting the bottom nailing cycle.

Fig. 1'7 is an enlarged fragmentary cross-sectional view taken on the line Il--l'l of Fig. 10 and illustrates the resilient toggle actuating links and the means for actuating the same.

Fig. 18 is an enlarged fragmentary side elevational view of the-nailing machine of the invention in the area indicated by line IS-IB of Fig. 1.

Fig. 19 is a diagrammatic sectional view taken on the line I9-I9 of Fig. 18 showing the box length gauging wedge cam during a nailing cycle.

Fig. 2O is an enlarged fragmentary vertical sectional detailed View taken on the line 25--25 of Fig. 5 and illustrating the Work hold down pad and punch bridge release mechanism.

Fig. 2l is an enlarged fragmentary sectional detailed view taken on the line v2-|2| of Fig. 20 and shows a nail driver bridge releasing device in released position and with the downward movement of the driver bridge interrupted with the latter in an elevated position above the structure normally supporting the same.

Fig. 22 is a sectional view taken on the line 22-22 of Fig. 21.

Fig. 23 is a diagrammatic View illlustrating the position of the nailing table supporting cam at the beginning of the first side'nailingcycle.

Fig. 24 is a View similar to Fig. 23 showing the` position of said cam at the beginning of `the bottom nailing cycle.

Fig. 25 is' a view similar to Fig. 24 and showing the nailing table supporting cam as positioned at the beginning of the second side nailing cycle.

Fig. 26 is ak perspective View of an egg case which is the type of box which the illustrated embodiment of the invention is designed to manufacture.

Fig. 27 is a View similar toY Fig. 13 in which the clamping means of the invention for clamping one of the heads o f the box being made is illustrated with its parts disposed as during the first of three nailing cycles required for'the manufacture of a box, this view illustrating the action of the clamping members when no -cleat is disposed between these.

Fig. 28 is a View similar to Fig. 2'7 illustrating the parts of the clamping means 'in clamping relation with said head during the second of said three nailing cycles duringwhich a cleat is disposed between the clamping'members.

Referring specically to the drawings, and particularly to Figs. 1, 2, and 3, the invention is here shown as embodied in a semi-automatic nailing machine 30, having a main frame 3|, including a base 32, and side standards v33 and 34, the standards being connected at their upper ends by a head member 35. The base 32 has a bearing standardy 36 carrying a bearing 31. The base 32 also has a motor platform 38 on which is mounted an electric motor 39, having a sprocket pinion 40.

Each of the standards 33 and 34 is provided with a main crank shaft bearing 45 near its lower end, vand a vertical slideway 46- nearA its upper end. Secured to the front edge of the side standards is la bearing 41. Secured for vertical adjustment to each of the side standards 35 and 34 by cap Screws 48 is a nailing table mount 49 carrying a. nailing table cam shaft bearing 5U.

Each of the nailing table mounts '49 has vertical slideways 55 (Fig. 5) formed along opposite edges therein, and a bracket 55 extends Aupwardly and rearwardly therefrom to lterminate in a bearing 3i. Also provided on each table mount 49 is a small bearing 58 and a pair of table stops 5S which are secured to the support by cap screws S0.

Extending rearwardly from a lower Apor-tionof side standard 34 is a gear casing "65 (Fig. 2) which provides bearings for fa jack shaft .66 carrying a chain sprocket |51 and a gear pinion 68. Shaft 65 also has a gear pinion 69 which is connected by a gear train 'i0 housed in gear casing @5to a shaft "H carrying a-crank 12.

lener 88, carrying an idle roller 89.

The chain sprocket 6i is connected to the chain pinion 4D by a chain 'i3 and rotates freely on the shaft |36. The sprocket 6l embodies a clutch l5 (Fig. l) for connecting this sprocket With shaft 66, said clutch being controlled by a foot pedal 76 mounted on the base 32.

Journaling in bearings 45 (Figs. 1, 2 and 3) is a- `crank shaft 8E] on one end of which is mounted a crank 8| (Figs. 1 and 3) and on the other end a master gear 82 (Fig. 2), the latter meshing with gear pinion 68.

The. shaft 8,0 also has chuck frame shifting cams 83 and a sprocket 84.

Fixedin bearings 4l' (Fig. 1) is a shaft 85 rotatively carrying arms 86 (Figs. 2 and 3) having cam follower rollers 8l (Fig. 7) which rest on cams: 83. Fixed. on shaft is a chain tight- Also carried on the shaft 85 isa spring clip Si).

Journaling in bearings (Fig. l) is a cam shaft Ill() (Fig. '7) to which is fixed a sprocket IBI, Ycams |52, and' a cam |53. Cams |02 have equal arced segmentsV m4, |05, and |06. (Figs. 5, 23, 24, and 25.)

Nailing table Sliding on the nailing table mounts 42 is a nailing table li' (Figs. l, 4 and 5). This table includes front and rear bars |98 and |29 which are held together by two cross members H0 secured' thereto by cap screws |.I|. Each of the members It@ provides bearings H2 and H3 for trunnions H4 and H15 of a cam follower roller H6, each of which rollers r-ides on one of the cams |52.

The table kit? is thusv supported by the cams |52, opposite endsV of the bars |58 and |09 sliding in the slideways 55, as the table |21 is raised or lowered by rotation ofcarnshaft |90.

The table IM (Fig. 5) is covered by a sheet metal plate Il'i lwhich is secured in place by bolts H8, extending; upwardly through clamp bars H'Q' and into three anvils |23 which lie transversely across the table |21 in the planes of the three heads of the box which the machine 3@ is designed to manufacture.

The use ofl tabie stops 59 (Fig. 5) in the operation of Ithemachine Sit is optional. These stops are employed to support the table EST in its lowermcst position when making a box requiring the lowermost position for the table itil, to be above the lowermost position which this table would have when the rollers H5 ride on the segments it of .cams |1132.

Trained about the sprockets t4 and lili and the idle roller ,81S (Fig, '2.) is a chain |25 through whichthe shaft Iii@ is driven at a one to three ratio by the shaft 3|).

C'huckjramev Pivotally connected to the arms 3.5 (Fig. l) are link heads |25 which extend outwardly through yholes l2? (Figs. 2 and 3) yin the side standards 33 and 34 and are rigidly connected to the lower ends of links |23, the upper ends of which connect with bosses |29 which extend outwardly through the openings of slideways 46 from a rectangular cast iron chuck frame |31). The bosses |29 slide in the slideway 45 thereby keeping frame |32 aligned during its vertical move-ment in the operation of the machine.

The chuck frame |36 carries three banks |32 -ofnail chucks |33 (Fig. 1) which are supported on bars |34, the opposite ends of which are secured by clamps |35 to the front and rear members |35 and |31 of the chuck frame |35. Mounted between adjacent chucks |373, near the opposite ends of each of the banks |32, are pressure pads |49 (Figs. 20 and 21) each of which comprises a block of metal approximately the same width as the chucks, having a slot |42 with which a bore |43 connects. Shoulders |44 are provided just above the slot |42, the pad |40 slidably tting between the bars |34 so that said shoulders engage said bars. A notched key |45 extends through the slot |42 and fits upwardly against and between the bars |34, this key being held in place by a stiff compression spring |41 which is extended upwardly through the bore |43 and retained in place by a cotter |48, a hole for receiving which extends through the lower end of the pad |40.

The structure of the nail chuck |33 is not Ashown in detail as this is well known in the nailing machine art.

Extending upwardly from opposite ends of the chuck frame |39 are heavy slide shafts |49 (Fig. 1) and straps |59 (Figs. l, 2, 3, and 5) the upper ends of which support a horizontally disposed frame |5| (Fig. 1) on which nail receiving cups |52 are carried. Connecting each of the cups |52 with one of the nail chucks |33 is a flexible nail conduit |53.

Driver frame Pivotally connected at their lower ends to pins |58 provided on the crank 8| and on the master gear 82 are pitmans |59 and |90 (Fig. 1). The upper ends of these pitmans connect to slide bosses |6| which extend outwardly from a rectangular driver frame |62 through guide slots 48 (Figs. 2 and 3) in standards 33 and 34. This frame has front and rear members |53 and |34 (Figs. 5 and 9) which are connected by end members |65 on which bosses |E| are formed. End members |65 are apertured vertically to slidably receive slide shafts |48. Driver frame members |63 and |64 have inside lower ledges |56 (Fig. 5) upon which are supported three driver bridge assemblies |51 (Fig. 9) each of which is disposed above and in vertical alignment with a corresponding chuck bank |32 (Fig. 20).

Each assembly |51 includes a driver bridge frame 88 having a pair of side members |69 which are held in parallel spaced relationship by their being welded at their opposite ends to attaching blocks |10 (Fig. 2l).

Each block |10 and the adjacent ends of members |99 are cut out so as to extend under the adjacent ledges |69. End portions of the members |89 are iurther notched as at |1| and |12 to form shoulders |13 against which legs |14 (Fig. 22) of a U-shaped clamp plate |15 rest, as this plate is pulled downwardly by a screw |18 extending up through a hole |11 in block 10 and threadedly received in a tapped hole provided therefor in said clamp plate. Each block |19 also has a notch |80 cut in an upper inner corner thereof.

. Mounted on each of the opposite ends of each driver bridge frame |60 on a pin |8| (Fig. 21) extending therethrough is a releasable holddown device |82. Each device |82 is in the shape of a bell crank and includes side plates |83 lower ends of which receive opposite ends of pin |8| and are held in spaced relation by a plate |84 (Fig. 20) welded between their upper extremities. The plate |84 has a screw |85. Pivotally mounted on a heavy pin |83, supported at its opposite ends on plates 83, is a hold-down roller |81. Disposed between the plates |83 and welded thereto at its opposite ends is a stop pin |88.

Slidable vertically in the space between side members |69 of each driver bridge frame |68 is a driver bridge |93. This bridge has a notch |94 cut from each lower end corner thereof to accommodate itself to the block |10 (Fig. 21). Secured to the upper face of each punch bridge |93 at each end thereof by a cap screw |95, and held against rotation by pins |96, is a stop plate |91, the latter over-lapping end portions of members |69 (Fig. 22) so as to support said driver bridge |93 on said members when the machine 39 is at rest and there is no upper pressure against the driver bridge |93. When this is the case, the releasable hold-down devices |82 are free to rock inwardly about the axes of the pins |8| until the stop pins |38 engage outer ends of plates |91 (Fig. 5). This brings the rollers |81 over the outer ends of plates |91 so as to hold opposite ends of the driver bridge |93 downwardly against the driver bridge frame |68 asso-A ciated therewith.

Each driver bridge |93 has a re-entrant groove 205 extending lengthwise along its lower edge. This groove slidably receives a plurality of driver head blocks 29B which are held in said groove by a removable plate 201. Each block 2%06 is apertured to receive the round upper end 298 of a square nail driver 299 which extends slidably downwardly into one of the nail chucks |33. Each driver is held in place in its block 205 by an Allen screw 2|0. Each of the pads |40 carried by the chuck frame |38 in a chuck bank |32 is located just beneath the inner edge of a plate |29. Located at the corresponding end of the driver bridge assembly |81 immediately thereabove and provided in 'the driver bridge |93 of said assembly in alignment with said pad |42, is a vertical hole 2|! in which a tappet rod 2|2, having a head 2l3, slides vertically.

Referring now to Figs. 5, 6, and 9, such driver assembly |81 provided with a rebound device 2|8. This includes a pair of threaded studs 2|9 (Fig. 6) which are provided on members |89 at center points therein and extend upwardly through a tie bar 228 and receive nuts 22| to hold said bar down and coniine a heavy short compression spring 222 between said bar and the driver bridge |93 of said assembly. Secured at its opposite ends to screws of the devices |82 at opposite ends of each 'assembly |61 is a coiled spring 223, the function of which is to return devices 82 to their hold-down positions as shown in Fig. 5.

Nail feed Mounted on the frame head member 35 is a nailfeed 238 including two units 23| (Fig. l). Each of these units has a base 232 on which a nail pan 233 is pivoted to deliver nails to nail runs 2134 yand from these through nail picking devices 235 to cups |52 from which conduits |53 deliver the nails to chucks |33. The pans 233 are swung up and down by links 236 and arms 231 on shafts 238 having gear sectors 239 meshing with similar sectors 249 (Fig. 2) on a shaft 24| which is rocked continuously by an arm 24.2 thereof which is connected by a rod 223 to the slowly rotating arm 12. (Fig. 2.)

The picking devices 235 are actuated by rods 250 which pass through ears 25| on driver frame |62 (Fig. 2) and carry springs 252 and collars l:253 for yieldably transmitting vertical movement of the driver frame to said devices causing them to selectively pick nails and deliver these to certain of the chucks |33 during the concluding portion of each nailing cycle.

member 368 which is always parallel with back edge 383 of member 38|.

Clamp arm 306, at the opposite end of the machine from clamp arm 38|, lacks a jack screw such as the jack screw 345 of arm 36| but otherwise has a structure which is a reverse duplicate of that of arm 30| just described. When referring hereinafter therefore to any part of arm 396 having a corresponding element in arm 30i, use will be made of the reference character applied to the latter element, with prime attached.

Actuation of the members 33i and 38| of the clamp arms 36| and 306 to shift members 368 and 368' outwardly and inwardly in the operation of the machine 39, is accomplished by the cam |03 which, as seen in Fig. 5, has lobes 395 and 396 which are spaced by a short dwell 391 and a long dwell 398. Journalling in bearings 58 (Figs. 1 and is a shaft 399 on which is fixed an arm 400 having a cam follower roller 49| which rides on theV cam |93 and which is connected by a spring 462 to the spring clip S9 so as to hold roller 46| against said cam. Also fixed to shaft 399 are arms 410 through the apertured ends of which extend rods 4| each of which has collars 4i? and 4|3 (Fig. 5). Coiled about eachV rod 41| between its collar 4 I2 and arm 4 0 is an expansive spring 4|4. The upper ends of rods 4| l pivotally connect with the arms 339 and 338 of bell cranks 331 and 331. It is thus seen that with the rotationof shaft |06, the roller 40|, riding onto lobe 395 or 396, swings arm 4I0 upwardly, rotates bell cranks 331 and 331 and shifts the extension members 368 and 368' of the arms 30! and 386 inwardly towards each other and that each time the roller 46| rides off of one of said lobes into the dwell 391 or 398 spring 452 pulls arm 408 downwardly thereby retracting wedge members 38| and 391 and permitting springs 388 and 380' to retract members 368 and 368 to their retracted positions as shown in Figs. 5 and 11.

Of the remaining clamp arms, arms 362 and 304 are alike and arms 303 and 305 are reverse duplicates of arms 302 and 364. A description of arm 332 will therefore suffice to indicate the structure of all of this group of inside clamp arms.

Clamp arm 302 has a body 4|1 which is a reverse duplicate of body 3|1 of clamp arm 30| excepting that the oor 42| thereof (Figs. 11 and 13) has recesses 422 and 423 cut therein to provide horizontal slide faces 424 and 425 and a shoulder 426 along the outer edge of face 425. The body 4| 1 includes a left side wall 421 having vertical pressure faces 428 and 429 and a bead 430 opposite the latter face at the lower edge of said side wall (Fig. 13).

Secured by cap screws 435 to the floor 42| and spaced fromthe latter by blocks 436, 431, and 438 is a cover plate 439. The floor 42| is provided with bosses 445 having tapped holes for receiving cap screws 446 which secure in place a side wall 441. Tapped holes are provided in this wall to receive spring tension adjusting screws 448 having set nuts 449. Spring follower caps 450 are provided on inner ends of the screws 448, these caps extending into bores 455 provided in nail diverting plungers `456 to trap compression springs 451 therein. Each plunger 456 has a lug 458 which limits the response of said plunger to said spring so that the base lines of serrated teeth 463 lie in the vertical plane of vertical faces 428 and 429. Formed on the left side wall 421 of clamp arm 302 and extending under 'said arm are bosses 459 and lugs 46.) which are aperturedV vertically to receive pivot pins 46|, the latter being secured in place by set screws 462.

Inasmuch as the structure of clamp arm 384 is identical to that of clamp arm 302 and the structure of clamp arms 303 and 305 are identical to, although reverse duplicates of, the structure above described of clamp arm 302, subsequent reference to the details of arms 303,. 304, and 395 will be by use of the same reference characters which are above employed in described corresponding details of clamp arm 302.

Mounted on the side wall 421 of each of the clamp arms 302, 303, and 305 isa box head stop 410 (Figs. 10, 13 and 15) each of which is in the form of a clamp extending from said wall into the space between this and the next adjacent clamp arm and having a clamp screw 41| which engages the back face of said wall above the bead 430 thereof to hold said stop in place. Y Screwed snugly into a threaded aperture provided horizontally in the block 3|0 of each of clamp arms 302, 304, and 306 is a stop screw 412 (Fig. 10) the purpose of which is to limit the approach of the arms having these screws to the adjacent clamp arms paired respectively therewith, the reasonV for this being made clear hereinafter.

Mounted on shaft 261 in the space between arms 302 and 303 (Fig. 17) and in the space between arms 384 and 305 (Fig. 10) are collars 419 each of which has a pair of short arms 460, which receives therebetween aswivel block 48|, pivotally connected therewith by a bolt 482.` lfm-Y bracing the block 48| and pivotally connected with it by a bolt 483 is a clevis 484 which is tapped to receive a threaded rod 485, the adjusted posi-- tion of which in said clevis is fixed by a lock nut 486. The rod 485 has a head collar 481 welded on its opposite end and extends through a bore 488 in the crotch of yoke 489, the arms of which receive and are pivotally connected by a bolt 490 to a block 49| having a pin 492 extending upwardly therefrom. Screwed onto the threaded portion of rod 485 is a nut 495. Trapped between said nut and said yoke 489 are spring centering washers 496 and a compression spring 491 (Fig. 17).

Located over each of the assemblies just described is a toggle connector 500 which includes a channel member 50| to opposite ends of Ywhich are welded upper and lower plates 592 and 563. These plates at the front end of the connectors 500 are apertured to pivotally receive the pin 492, the upper end of the latter then receiving a washer 504 and a cotter 505 to retain this pin in place. Passing vertically through the plates 562 and 503 at each end of the connect-or 530 are bolts 506 and 501. Pivotally receiving the bolts 506 (Figs. 10 and 14) and the pins 46| of the clamp arm on the adjacent side of said connector are parallel links 508, which are of fixed length. Pivotally receiving bolts 581 and pins 46|I, of the clamp arm on the corresponding side of said connector, are parallelturnbuckle links 589 which may be extended or retracted by turning a turnbuckle screw 5I0 thereof which threadedly connects link heads 5|| and 5| 2.

Fixed on the shaft 266 and extending outwardly and upwardly therefrom is a pair of short arms 5|8 (Figs. 2, 10, and 15). These arms carry inwardly bent stop rods 519 and provide bearings for a shaft 520 on which are xed hub collars 521 

